A solid-phase mechanochemical technology of production of polycrystalline InSе intercalated with Ni up to 1.25 at. % has been developed. The x-ray and phase analyses of the produced NixInSe samples confirm their homogeneity and demonstrate a nonmonotonic Ni-content dependence of the lattice constant along the axis normal to the layers. Analysis of the low-temperature (77 K) impedance response within the frequency region 10–3–106 Hz shows a good correlation between the change in interlayer distance and in the band conductivity observed with increasing Ni concentration. However, the Ni concentration dependence of specific magnetization demonstrates an irregular increase at x ∼ 1 and does not coincide with the former. Such behavior is explained by the proposed theoretical model, which at the same time unveiled the mechanism behind the increasing contribution of free carrier concentration to conductivity – hybridization of electron orbitals of guest nickel and the lattice layers.

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The theoretical and experimental study of low-temperature heat capacity of InSe intercalated by nickel as a function of temperature has been carried out in range 0.3-30 K. The effect of intercalation by nickel on phonon heat capacity (C ph ) of InSe has been investigated. Two peaks observed in relative change of phonon specific heat (∆C ph /C ph ) suggested non-Debye excess in heat capacity for all intercalated Ni

The intercalation compounds of NixInSe (x  0; 0.25; 0.5; 0.75; 1.0; 1.25) were produced by the method of direct synthesis of components in quartz ampoules. These compounds are characterized by the formation of discrete nanoislands from the "guest" component as well as their reproduction with the formation of fractal nets. The inductive response at x  0.25, x  0.75, x  1.25, which for the indicated values of x has different intensity and frequency manifestation has been revealed for these structures. An impedance analysis of electrical current passage and its comparison with the data of temperature dependence of electrical conductivity has been carried out. It was found that the linear contribution to the heat capacity from the electrons at the lowest temperatures disappears as a result of intercalation with nickel, and at temperatures below Debye temperature the temperature dependence of the specific heat does not correspond to the expected law of T 2 ÷ 3 for the quasi-twodimensional systems. The revealed out of the ordinary effects can be explained by the change in the fractal structure of the clustered nickel guest subsystem.

The mechanisms of the photoelectretic effect appearing on Ni intercalation GaSe were studied. The presence of the photoelectretic effect for such an object of investigation can be explained by the estimation that in Ni intercalated GaSe , the nonequilibrium electrons and holes excited by light occurred on an asymmetric potential well.